Justin Houston wasn't supposed to be on the field at the end of the game.

Chiefs coach Andy Reid had pulled most of his starters in the lopsided win against St. Louis, and his star pass rusher was supposed to be next to him on the sideline. But when Josh Martin hurt his hamstring late in the fourth quarter, Houston quietly slipped back onto the field

Naturally, he went ahead and bagged one more sack.

"He kind of snuck in there at the end of the game," Reid said with a grin. "I just thought all along the front, we played very aggressive. We played an aggressive game."

Nobody more than Houston, who had three of the seven sacks that Kansas City racked up against Rams quarterback Austin Davis. In fact, No. 50 was in the youngster's face so often Sunday that it seemed as if Houston was lining up in the offensive backfield most of the afternoon.

"It was definitely a factor in the game," Davis said.

Houston's three sacks on Sunday gave him 10 for the season, passing Denver's Von Miller for the most in the league. It also put him on pace to set the Chiefs franchise record, which has been held by the late Derrick Thomas since he recorded 20 of them during the 1990-91 season.

The fourth-year pro also had 10 sacks through the first seven games a year ago, including a memorable 4 1/2-sack game in Philadelphia. Houston picked up another the following week against Cleveland, but then was shut out each of the next three weeks.

In the last of those games, a loss to AFC West-rival San Diego, Houston dislocated his elbow and missed the final five games of the regular season. He returned in time for the Chiefs' playoff game in Indianapolis, but a bulky brace on the elbow limited his mobility. He still managed to get to Colts quarterback Andrew Luck in a 45-44 defeat that ended the Chiefs' season.

"That's behind me," Houston said of last season. "I'm worrying about this year."

So far, several opponents have made things easy on him.

In the case of the Rams, they fell behind by a large margin early, and that forced them to throw the ball more than normal. Suddenly, Houston didn't have to worry about the run game.

Then there were the injuries. The Rams lost star left tackle Jake Long to a knee injury, right guard Rodger Saffold to a shoulder injury and played for a while without center Scott Wells, who left with an undisclosed injury. Combine their replacements with a rookie starter at left guard in Greg Robinson and, well, the Chiefs' pass rushers were left to salivate.

That went doubly for Houston when he sneaked back on the field in the fourth quarter.

"Without a doubt, for a sack guy that loves to put pressure on the quarterback, six minutes left in the game, you're up big like that — you know what time it is? It's time to pin your ears back," he said. "Any time we know they have to pass, we can pin our ears back."

The superb play of Houston and the rest of his pass-rushing cohorts is a big reason why the Chiefs have had one of the best pass defenses in the NFL, despite losing Pro Bowl cornerback Brandon Flowers in the offseason and Pro Bowl safety Eric Berry to an injury several weeks ago.

They certainly didn't hurt their ranking against St. Louis.

Davis was just 15 of 25 for 160 yards on Sunday. When you combine the negative yardage from his seven sacks, his net passing total dropped to a meager 116 yards.

"It's more of a team effort," Houston said with a shake of his head. "Any time you make the quarterback hold the ball the front four can get pressure."

Still, the personal accolades are sure to flow in if Houston keeps up his current rate. He would finish with 23 sacks this season — rounding up to the nearest half-sack, of course. And that would eclipse the NFL's single-season record of 22 1/2 set by Michael Strahan in 2001.

Not that Houston is thinking about records, especially with nine games to go.

"I'll worry about that at the end of the season," he said. "My goal is to get as many sacks as I can every game, that's my job. Every time I can put pressure on the quarterback, that's a plus."